Non-aqueous electrolyte secondary battery

Abstract

In this non-aqueous electrolyte secondary battery, a positive terminal and a negative terminal extend in a first direction, protrude from a laminated cell stack, and are provided so that a center line is interposed therebetween, the center line passing through a midpoint of both ends of the laminated cell stack in a second direction orthogonal to the first direction and extending in the first direction when the laminated cell stack is seen in plan view, and a first terminal with higher heat dissipation efficiency among the positive terminal and the negative terminal is provided in a location closer to the center line than a location of a second terminal with lower heat dissipation efficiency among the positive terminal and the negative terminal.

What is claimed is: 
     
       1. A non-aqueous electrolyte secondary battery comprising a laminated cell stack including one or more layers of:
 a positive electrode having a positive electrode current collector to which a positive terminal is connected; 
 a negative electrode having a negative electrode current collector to which a negative terminal is connected; and 
 a separator disposed between the positive electrode and the negative electrode, wherein: 
 the positive terminal and the negative terminal extend in a first direction orthogonal to a stacking direction of the laminated cell stack so as to protrude from one side of the laminated cell stack, the one side extending in a second direction orthogonal to the first direction and the stacking direction, 
 a center line extends in the first direction so as to:
 pass through a midpoint of the one side of the laminated cell stack when the laminated cell stack is viewed in plan view, and 
 be interposed between the positive terminal and the negative terminal, 
 
 a first terminal with higher heat dissipation efficiency among the positive terminal and the negative terminal is provided in a location closer to the center line than a location of a second terminal with lower heat dissipation efficiency among the positive terminal and the negative terminal, 
 the one side of the laminated cell stack is divided by a first division line extending in the first direction into: (i) a first side having an area proportional to E 1 /(E 1 +E 2 ), and (ii) a second side having an area proportional to E 2 /(E 1 +E 2 ), where E 1  represents a value of the heat dissipation efficiency of the first terminal, and E 2  represents a value of the heat dissipation efficiency of the second terminal, 
 a first terminal center line that extends in the first direction and passes through a center of the first terminal coincides with a first side center line that extends in the first direction and passes through a center of the first side, and 
 a second terminal center line that extends in the first direction and passes through a center of the second terminal coincides with a second side center line that extends in the first direction and passes through a center of the second side. 
 
     
     
       2. The non-aqueous electrolyte secondary battery according to  claim 1 , wherein:
 an inter-terminal region of the one side of the laminated cell stack extends a distance L in the second direction between a midpoint of the first terminal and a midpoint of the second terminal, 
 the inter-terminal region is divided at a ratio of E 1 :E 2  by a second division line extending in the first direction, and 
 the second division line is positioned within a range of: a position shifted from the first division line toward the first terminal by a distance equal to W×E 1 /E 2 ×0.3 to a position shifted from the first division line toward the second terminal by a distance equal to W×E 1 /E 2 ×0.5, where W represents a width in the second direction of the laminated cell stack. 
 
     
     
       3. The non-aqueous electrolyte secondary battery according to  claim 2 , wherein a position of the first division line and a position of the second division line coincide with each other. 
     
     
       4. The non-aqueous electrolyte secondary battery according to  claim 1 , wherein cross sections of the positive terminal and the negative terminal are quadrangular, and heat dissipation efficiencies of the positive terminal and the negative terminal are shown by a formula (1) each independently, when a thickness of the terminals is shown by t, a width of the terminals are shown by w, thermal conductivity of the terminals are shown by λ, and heat dissipation efficiency of the terminals is shown by E,
     E=t×w×λ   (1).
 
 
     
     
       5. The non-aqueous electrolyte secondary battery according to  claim 1 , wherein when a width in the second direction of the laminated cell stack is referred to as W, a width of the first side is shown by W×E 1 /(E 1 +E 2 ) and a width of the second side is shown by W×E 2 /(E 1 +E 2 ). 
     
     
       6. The non-aqueous electrolyte secondary battery according to  claim 1 , wherein a width of the first terminal and a width of the second terminal are the same. 
     
     
       7. The non-aqueous electrolyte secondary battery according to  claim 1 , wherein:
 the one side of the laminated cell stack extends in the second direction between a first end on a first terminal side and a second end on a second terminal side, and 
 a distance between the first terminal and the first end is not equal to a distance between the second terminal and the second end. 
 
     
     
       8. The non-aqueous electrolyte secondary battery according to  claim 7 , wherein the distance between the first terminal and the first end is greater than the distance between the second terminal and the second end. 
     
     
       9. The non-aqueous electrolyte secondary battery according to  claim 1 , wherein the laminated cell stack is a quadrangle or a quadrangle having corner portions formed in an arc shape in plan view. 
     
     
       10. A non-aqueous electrolyte secondary battery comprising a laminated cell stack including one or more layers of:
 a positive electrode having a positive electrode current collector to which a positive terminal is connected; 
 a negative electrode having a negative electrode current collector to which a negative terminal is connected; and 
 a separator disposed between the positive electrode and the negative electrode, wherein: 
 the positive terminal and the negative terminal extend in a first direction orthogonal to a stacking direction of the laminated cell stack so as to protrude from one side of the laminated cell stack, the one side extending from a first end to a second end in a second direction that is orthogonal to the first direction and the stacking direction, the first end being closer to the positive terminal than the negative terminal, and the second end being closer to the negative terminal than the positive terminal, 
 a first distance between the first end and the positive terminal is different from a second distance between the second end and the negative terminal, 
 a center line extends in the first direction so as to:
 pass through a midpoint of the one side of the laminated cell stack when the laminated cell stack is viewed in plan view, and 
 be interposed between the positive terminal and the negative terminal, 
 
 a first terminal with higher heat dissipation efficiency among the positive terminal and the negative terminal is provided in a location closer to the center line than a location of a second terminal with lower heat dissipation efficiency among the positive terminal and the negative terminal, 
 the one side of the laminated cell stack is divided by a first division line extending in the first direction into: (i) a first side having an area proportional to E 1 /(E 1 +E 2 ), and (ii) a second side having an area proportional to E 2 /(E 1 +E 2 ), where E 1  represents a value of the heat dissipation efficiency of the first terminal, and E 2  represents a value of the heat dissipation efficiency of the second terminal, 
 an inter-terminal region of the one side of the laminated cell stack extends a distance L in the second direction between a midpoint of the first terminal and a midpoint of the second terminal, 
 the inter-terminal region is divided by a second division line extending in the first direction into: (1) a first inter-terminal region having an area proportional to E 1 /(E 1 +E 2 ), and (2) a second inter-terminal region having an area proportional to E 2 /(E 1 +E 2 ), and 
 a distance between the first division line and the second division line is equal to or less than a value represented by the formulae WxE1/(E 1 +E 2 )×0.5, where W represents a width in the second direction of the laminated cell stack. 
 
     
     
       11. The non-aqueous electrolyte secondary battery according to  claim 10 , wherein the laminated cell stack is a quadrangle or a quadrangle having corner portions formed in an arc shape in plan view. 
     
     
       12. The non-aqueous electrolyte secondary battery according to  claim 10 , wherein a distance between the first division line and the second division line is equal to or less than a value represented by the formulae W×E 1 /(E 1 +E 2 )×0.3. 
     
     
       13. The non-aqueous electrolyte secondary battery according to  claim 10 , wherein a distance between the first division line and the second division line is equal to or less than a value represented by the formulae W×E 1 /(E 1 +E 2 )×0.2. 
     
     
       14. The non-aqueous electrolyte secondary battery according to  claim 10 , wherein when a distance between the center line and a center of the first terminal is referred to as d 1 , a distance between the center line and a center of the second terminal is referred to as d 2 ,
 a value obtained by the formula (E 1 /E 2 )/(d 1 /d 2 ) is in a range of 0.7 to 1.5. 
 
     
     
       15. A non-aqueous electrolyte secondary battery comprising a laminated cell stack including one or more layers of:
 a positive electrode having a positive electrode current collector to which a positive terminal is connected; 
 a negative electrode having a negative electrode current collector to which a negative terminal is connected; and 
 a separator disposed between the positive electrode and the negative electrode, wherein: 
 the positive terminal and the negative terminal extend in a first direction orthogonal to a stacking direction of the laminated cell stack so as to protrude from one side of the laminated cell stack, the one side extending from a first end to a second end in a second direction that is orthogonal to the first direction and the stacking direction, the first end being closer to the positive terminal than the negative terminal, and the second end being closer to the negative terminal than the positive terminal, 
 a first distance between the first end and the positive terminal is different from a second distance between the second end and the negative terminal, 
 a center line extends in the first direction so as to:
 pass through a midpoint of the one side of the laminated cell stack when the laminated cell stack is viewed in plan view, and 
 be interposed between the positive terminal and the negative terminal, 
 
 a first terminal with higher heat dissipation efficiency among the positive terminal and the negative terminal is provided in a location closer to the center line than a location of a second terminal with lower heat dissipation efficiency among the positive terminal and the negative terminal, and 
 a width of the first terminal in the second direction is equal to a width of the second terminal in the second direction. 
 
     
     
       16. The non-aqueous electrolyte secondary battery according to  claim 15 , wherein the laminated cell stack is a quadrangle or a quadrangle having corner portions formed in an arc shape in plan view. 
     
     
       17. The non-aqueous electrolyte secondary battery according to  claim 15 , wherein when a distance between the center line and a center of the first terminal is referred to as d 1 , a distance between the center line and a center of the second terminal is referred to as d 2 , a value of the heat dissipation efficiency of the first terminal is referred to as E 1 , and a value of the heat dissipation efficiency of the second terminal is referred to as E 2 ,
 a value obtained by the formula (E 1 /E 2 )/(d 1 /d 2 ) is in a range of 0.7 to 1.5.